i) Field of the Invention
A technique of this disclosure relates to a capacitor such as an electric double layer capacitor and an electrolytic capacitor.
ii) Description of the Related Art
In a capacitor such as an electric double layer capacitor and an electrolytic capacitor, an electrolyte contained in a capacitor element stays in a case. Such a capacitor includes a gas releasing mechanism. This gas releasing mechanism discharges gas accumulated in an exterior package case at the time of drive of the capacitor. For this gas releasing mechanism, for example, a safety valve with gas permeability is used.
Regarding a capacitor of this type, it is known that a Y-shaped projection is formed on a sealing plate to avoid contact of electrolytic solution leaking out at the time of operation of the safety valve with an external terminal by the projection on the sealing plate (e.g., Japanese Utility Model Application Laid-Open Publication No. 55-129447).
It is known that when a cap of a resign case is fused with a lower case by ultrasonic waves, electrolytic solution flowing out from a polarizable electrode due to vibrations is blocked by a blocking wall disposed on the cap to prevent the electrolytic solution from contaminating a fused portion (e.g., Japanese Laid-Open Patent Publication No. 2011-100998).